RESUMEN
Phytochemical investigation of the lipids extracted from seeds of Cannabis sativa by GC-MS showed 43 cannabinoids, 16 of which are new. The extract is dominated by Δ9-tetrahydrocannabinolic acid (A) and its neutral derivative trans-Δ9-tetrahydrocannabinol-C5 (THC) Cis and trans-Δ9-tetrahydrocannabinol-C7 isomers with an ethyl-pentyl branched chain together with minor amounts of trans-Δ9-tetrahydrocannabinol with a methyl-pentyl C6 branched side chain were identified as new natural compounds. Four cannabichromene isomers with a C5 side chain are postulated to be derived from the double bond migration at the terminal isoprenyl unit. C7 cannabichromene together with the neutral and acidic forms of cannabinol-C7 were also detected. The mass spectrum of these homologues as trimethylsilyl (TMS) derivatives are presented, and the fragmentation patterns are discussed.
Asunto(s)
Cannabinoides , Cannabis , Dronabinol , Cromatografía de Gases y Espectrometría de Masas , Espectrometría de MasasRESUMEN
It has been studied an immature coal (leonardite) as an adsorbent for removing PAHs [fluorene, pyrene, benzo(k)fluoranthene, benzo(a)pyrene and benzo(g,h,i)perylene] from water. To determine the efficiency of leonardite as an adsorbent of PAHs, factors such as pH, contact time and equilibrium sorption were evaluated in a series of batch experiments. There were no significant differences in the removal percentages for the various pH values studied, except for fluorene. The adsorption of fluorene was higher at lower pH values. The equilibrium time was reached at 24h. At this time, more than 82% of the pyrene, benzo(k)fluoranthene, benzo(a)pyrene and benzo(g,h,i)perylene had been removed. During the first 2h, the adsorption rate increased rapidly. After that time, however, there was a minor decrease. Equilibrium data were fitted to Freundlich models to determine the water-leonardite partitioning coefficient. Physical adsorption caused by the aromatic nature of the compounds was the main mechanism that governed the removal process. The polarity of the humic substances in leonardite may also have influenced the adsorption capacity.